Reciprocating pump type dispenser



y 1966 D. F. CORSETTE 3,249,259

RECIPROCATING PUMP TYPE DISPENSER Filed Aug. 5, 1964 I INVENTOR,

flouams F (0%5572'5 ATTORNEYS United States Patent 3,249,259 RECIPROCATING PUMP TYPE DISPENSER Douglas F, Corsette, Los Angeles, Calif., assignor to Calmar, Inc., Industry, Calif., a corporation of California g Filed Aug. 3, 1964. Ser. No. 386,930 19 Claims. (Cl. 222-182) This invention relates to molded plastic sprayers of the manually operated reciprocating pump type for dispensing liquids from portable containers, and is an improvement over the dispenser disclosedin the application of Robert D. Wise and Douglas P. Corsette, Serial No. 268,-

756 filed March 28, 1963, and of common ownership herewith.

In devices of the type exemplified in the said prior application, the-sealing means were rendered operative by displacement of the pump plunger to its outermost position. While the plunger spring projected the plunger toward such position, the size and strength of the spring were limited by the size of the pump chamber in'which it was housed. Therefore the thrust of the spring was supplemented by a protective cap having a cam means cooperating with the plunger to strongly raise it and retain it in its sealed position.

With this in mind it is an important object of the pres ent invention to improve such a dispensing pump structure by enclosing the plunger spring'in a telescoping housing separate from the pump chamber, the housing sections being carried by the plunger and cylinder of the pump respectively to permit elongation and contraction of the said housing as the plunger reciprocates. Such a housing serves the multiple purposes of protecting the enclosed portion of the plunger therein and the plunger spring from the atmosphere, and from contact with possible sources of contamination, while at the same time permitting the use of a considerably larger and heavier spring than was heretofore possible, without regard to or limitation by the size of the pump chamber. Conversely this also permits a very substantial reduction of the pump chamber to a minimum diameter and volume such as'to permit the rapid priming of the pump by minimum movement of the plunger. Also interpositioning of this extensible sealed housing between the pump chamber and the atmosphere,

, permit it to function as an effective barrier for isolating the pump chamber from communication with external sources of contamination or from loss of its contents by evaporation.

The spring may in fact be of sufficient size and strength as to overcome substantial friction between the plunger and stationary parts of the pump, thereby permitting the employment of closer than normal tolerances between these parts in order to minimize the loss by evaporation of fluid which is normally carried upwardly by the plunger through its associated guide bushings. Also by thus removing the spring from the pump chamber, it is normally maintained out of contact with the liquid passing through the pump, thereby decreasing the chances of contaminating the liquid either by chemical interaction with or corrosion of the spring or by any foreign substances on the spring. In the preferred embodiment of the invention the telescoping relationship between the said spring housing sections serves to accurately guide the plunger in its reciprocating motion.

'By reducing the volume of the pump chamber to a minimum, as is made possible by the present invention by virtue of 'the removal of the spring from the pump chamber, as well as by maintaining the diameters of the fluid passages of the pump at a minimum, it is possible to secure other highly important advantages including the minimizing of the water hammer effect such as is caused by the inertia of the column of liquid within said passages and pump chamber in pumps wherein the inlet 3,249,259 Patented May 3, 1966 valve is not positively seated at the end of each pump stroke. Such inertia tends to draw up undesired quantities of liquid past the pump, except in pumps such as illustrated in the preferred embodiment hereof, in which the valve is engaged and positively seated by the plunger at the end of each operative pump stroke. The continuing flow of this liquid toward the discharge opening of the plunger, where such opening is defined by a spray orifice, causes what is commonly termed fall out. Fall out is undesirable because it consists of particles of liquid expelled from the spray orifice after termination of the plunger stroke and under reduced pressures which result in an inferior spray pattern. Moreover with such minimum diameter pump chamber and passages there inherently results less elastic expansion of the plastic pump parts from the intermittent peak pump pressures, with the result that there is a reduction of the fall out that i would normally result from contraction of these expanded passages after the end of each stroke. It is recognized that reduction in cross section of the passages will normally involve a corresponding increase in velocity of the fluid passing through them, and that this, to some extent will offset the reduction of the fluid inertia or water hammer effect as above'mentioned. However it is found that the increase in frictional resistance to the fluid flow which simultaneously occurs, more than offsets this so that a beneficial result is obtainable.

It is a further object to provide such a pump having a reduced number of components capable of assembly in simplified manner and, specifically in which the several major components are all secured in assembled relation by a collar element capable of performing other functions as well.

Further objects are to provide fixed interconnections preventing rotary movement between the pump structure and the container to which it is applied, while permitting free rotation of the container cap with respect thereto,

.whereby the pump structure may be secured or held against rotation on the container while the cap is threaded onto the container, and/or while a protective cover is threaded onto the pump plunger.

It is afurther feature of the invention to provide such a device which is particularly adapted for use with liquids which may be either of a corrosive or highly volatile nature, or which may comprise medicines or the like which are to be kept in sterile condition, the pump structure serving to minimize the possibilities of contamination andloss either by leakage or by vaporization.

Further it is an object to provide an improved venting means for preventing an air lock in the portion of the pump cylinder above the piston, in which the venting means is automatically rendered operative by operation of the pump and is automatically sealed upon cessation of its operation. I

A still further object is to provide in association with such a pump structure a protective overcap removably threaded onto the pump plunger and in mutually sealing and shielding engagement with'a collar portion of the pump cylinder in a manner such that the sealing thrust between the overcap and the collar urges the latter toward its sealing relation with'the plunger.

Also it is an object to provide such a pump structure in which the cross sectional area of the pump size may be modified within substantial limits to vary the output, with minimumv changes in the pump on the mold by which same is produced.

The accompanying drawing and the following detailed description are given by way of example only to disclose the best mode presently contemplated of practicing the invention. This will involve various details which may be omitted or changed in obvious ways without departing from the invention.

in FIGURE 1.

FIGURE 3 is a section on the line 33 of FIGURE 1.

FIGURE 4 is a plan view of the structure shown in full.

lines in FIGURE 1 but with the supplemental sealing cover removed, and

FIGURE 5 is a greatly enlarged fragmentary detail" section taken in the same plane as FIGURE 1 and showing the details of the venting structure as defined by the interfitting portions of the pump cylinder plunger and collar.

Referring now in detail to the accompanying drawings, the reference numeral in FIGURE 1 designates the upper end portion of the container, here illustrated as a glass or plastic bottle having an externally threaded neck 11 defining the container mouth or outlet 12. Around the upper end of the neck exterior and just above the threaded portion thereof are provided a series of uniformly circumferentially spaced anti-rotation lugs 13 for cooperation with the pump cylinder C, as hereinafter described.

The container closure cap 14 may be of plastic or other similar conventional material having an internally threaded cylindrical skirt 15 and having its top formed with a central circular aperture 16 through which is disposed and supported the stationary portion, here designated in its entirety as the cylinder C, of a dispensing pump, the axially reciprocating plunger P of which projects upwardly through the open upper end of the cylinder C and above the container cap 14 to be actuated by inter mittent downward finger pressure on its upper end.

Except for the pump spring 17 and ball valve 18, it is contemplated that all parts of the pump structure hereinafter more fully described, will be formed by usual plastic molding operations from commercially available plastic materials having sufficient resiliency and elasticity that the several seals, the piston and the snap coupling structure as hereinafter described will all function efliciently for their intended purposes.

The pump cylinder C comprises a comparatively small diameter lower end portion defining a cylindrical pump chamber 20 communicating through an intake valve port 21 at its lower end with a conventional dip tube 22 formed integrally with this cylindrical portion and extending downwardly into the container contents in usual manner to a location near the bottom of the container 10. Surrounding the intake port is a usually conical valve seat 23 on which is operatively disposed the conventional ball check valve 18, adapted to permit intake or upflow of liquid into the pump chamber while preventing downward flow.

In accordance with usual practice, the ball valve 18 is actuated in response to the reciprocating movement of a piston 24, disposed for axial reciprocation within the pump chamber. The piston is carried at the end of a tubular piston rod 25 having part of'an axial discharge passage 26 extending completely therethrough and opening downwardly through'the piston into the pump chamber 20. At its upper end, this piston rod carries a preferably separately formed plunger head 27 which, in the present instance, is in the form of a spray head having a passage 28 communicating with and constituting an upward extension of the discharge passage 26 and communicating with the hereinafter described spray head passages to deliver the outdo-wing liquid through a radially presented dischargeorifice 30 in a suitable spray pattern.

The upper end portion 31 of the pump cylinder or barrel C comprises an enlarged diameter sleeve-like spring housing section, which is open at its upper end, and which communicates with the open upper end of the pump chamber, being integrally connected to the chamber by an annular shoulder 32 at its juncture therewith. Housing section 31 telescopically receives the depending skirt or housing section 33 of the plunger, to therewith define a substantially fluid-tight extensible spring housing, as more fully described hereinafter.

The pump spring 17 for reciprocating the plunger P encircles the piston rod 25 within this housing and has its lower end in abutment with the upper surface of the shoulder 32, which thus defines a spring seat, while the upper end of the spring abuts against a radial flange 34 formed around and integrally with the upper end portion of the piston rod.

Formed around the enlarged cylinder portion 31 adjacent its upper end is an integral radial supporting flange 35, adapted to rest on the upper end of the threaded container neck 11, and preferably provided with an annular sealing ring 36 for sealing engagement with the end of the neck. Depending from the flange is a marginal skirt 37 adapted to encircle the container neck 11 above the threads thereof and provided on its internally presented surface withanti-rotation lugs 38 arranged for interlocking reception between the lugs 13 of the container neck, to interlock the pump cylinder C and the container 16 against relative rotation.

The upper end extremity of the cylinder C above the flange 35 affords an upwardly projecting cylinder extension 40, which is rotatably received and centered through the circular opening 16 in the closure cap, to provide between these parts a rotary interconnection which permits free rotation of the container cap 14 so that it may be freely threaded onto and removed from the container 10 despite the action of the anti-rotation lugs 13 and 38 in maintaining the pump cylinder C and container 10 against relative rotation.

For securing the pump cylinder and container cap against substantial relative axial displacement, there is provided a retainer collar 41 having an integral radial flange 42 above the top of the cap so that the latter is confined between the two flanges 35, 42 and freely rotatable with respect to both. The collar 41 is axially received and retained in the enlarged upper end of the cylinder extension by any suitable means. A particularly suitable and eflicient such means, best shown in FIGURE 5, is exemplified by the interior and exterior snap rings 43 and 44 respectively formed as integral parts of the collar 41 and of the cylinder extension 40. In accordance with conventional practice, these snap rings are of such relative diameters that they must be forced past each other in assembling the parts. After their initial assembly, the interference between these parts will strongly resist their disassembly by relative upward displacement of the collar 41.

Moreover (still referring to FIGURE 5) it will be seen that the upper end of the cylinder extension 40 is snugly received within an annular downwardly presented sealing groove 45 within the collar flange 42 and in radial sealing abutment with the upwardly converging conically tapered outer wall 46 of the groove.

In accordance with the present invention, the pump spring 17 is completely housed within the axially expansi- -ble and contractable housing defined by the telescopically interconnected sleeves or sections 31 and 33 of the cylinder C and the plunger P. The depending plunger skirt 33, which functions as the inner member of this telescoping housing structure, is provided with a radially projecting annular rib 47 for abutment with the lower end portion of the collar 41' to limit the. upward stroke of the plunger, and to maintain the assembled relation of the plunger P and cylinder C.

For preventing relative rotation between the plunger P and cylinder C, the plunger skirt 33 is provided below the retainer or stop rib 46 with axially disposed splines 48 which are received and guided between cooperating splines 49 formed in the lower portion of the enlarged cylinder extension 31. The lower ends of these last mentioned splines are preferably provided with similarly downwardly and inwardly tapering portions 50 which center the lower end of the spring on its seat around the upper end of the pump chamber 20.

The plunger skirt 33 is slidably received and axially guided for reciprocation through the encircling collar 41 with suflicient clearance to define a vent through which air may flow incident to reciprocation of the telescopically connected sleeves or sections 31, 33 of the spring housing, though this vent will be closed by the interengaged annular plunger rib 47 and the collar 41 in the fully projected or raised position of the Plunger.

In addition to limiting the upward stroke of the plunger the engagement between the annular ri-b 47 of the plunger skirt and the collar 41, is relied upon to establish a seal for preventing escape of liquid contents between the collar and plunger skirt when the plunger is raised. For this purpose it will be seen in FIGURE 5 that the lower end portion of the collar 41 has an internally conically tapered surface 52 adapted for sealing engagement with the similarly tapered surface portion 53 of the rib 47, the upward convergence of both tapering portions, causing them to be pressed into tight sealing engagement by the expansive action of the plunger spring.

The foregoing features all contribute to the fluid tightness of the pump and container structure even though the latter be inverted or laid on its side.

For preventing an air lock within the telescoping housing 31, 33 incident to reciprocation of the plunger, it is desirable during operation of the dispenser to vent the interior of the spring housing to the interior of the container 10, preferably at a location which is normally above pose are designated 54, 55 and 56 in FIGURE 5. However when the dispenser is not in use, it is desirable to close off these vents and to prevent any intercommunication between the interior of the spring housing'and the container such as would permit liquid to enter the spring housing or to leak externally between the collar and plunger in the event of tilting or inversion of the contamer.

Obviously entry of liquid from the container into the spring housing is undesirable, since a portion of this liquid could then be forced upwardly between the plunger skirt 33 and collar 41 by the fluctuating air pressures created by expansion and contraction of the housing. Also it is likely that a portion of such liquid could pass downwardly beyond the piston into the pump chamber to mingle with the fresh liquid coming into the pump chamber. Thus in the event of contamination by contact with the spring or by chemical interaction therewith, such liquids could conceivably contaminate the liquids dispensed by the pump. Further of course the isolation of the pump spring from the liquids will be desirable in order to adapt the pump for dispensing liquids of a highly corrosive nature without damage to the spring.

The vent or venting means illustrated in FIGURE 5 includes the vent passage 54 opening radially outwardly through the sealing conical surface 52 of the collar 41 and into the annular clearance space 55 between this sleeve and the upper end portion of the lower spring housing or enlarged diameter portion 31 of the cylinder C, together with vent passage 56 through the cylinder 31, between annular space 55 and the interior of container 10. The annular space 55 is sealed at its upper end by the sealing engagement of the upper end extremity of the cylinder extension with the tapered wall 46 of the groove within the lower face of the flange 42, and

also by the interengaged annular retainer beads 43 and 44.

The intercommunication afforded by the annular pas-' plunger piston and cylinder to achieve the venting action.

It will be readily apparent that when the plunger P is projected upwardly or outwardly to its fullest extent by action of its spring 17, the conical sealing face of the stop rib around the plunger skirt will sealingly engage the correspondingly tapered sealing face 53 of the collar 41 over the vent passage 54 to securely close the vent 54, 55, 56 against entry of liquid into the spring housing in the event the container is tilted or inverted. On the other hand, during its normal use, mere depression of the plunger to initiate its operation will open the vent 54, '55, 56 to permit the venting action. Since the device will normally be operated in an erect position, in which position the vent Will communicate with the bottle interior at alevel well above the normal liquid level therein, it will be apparent that there is little danger of liquid entering the spring housing during such normal usage.

The dispensing head of the plunger, as earlier mentioned, is coupled to the upper end of the hollow piston rod 25 for reciprocation therewith, with its outlet passage section 26 in fluid tight communication and constituting a continuation of the piston rod passage 26. T 0 this end,

the upper end extremity of the piston rod 25 is tapered as shown at 58 (in FIGURE 1) for fluid tight sealing reception in a correspondingly tapered socket around the inlet end of discharge passage section 26', whereby the liquid moving upwardly through the plunger is delivered to the discharge orifice 30 which, in the present instance,

. is directed radially. By joint reference to FIGURES 1 and 4, it will be apparent that the upwardly presented axial end of the plunger head is formed to provide a slightly axially inclined finger piece 60 bounded by a marginal rim 61 for comfortable reception of the tip of the users finger, by which intermittent operating pressure is applied to the plunger. Also, this finger piece 60 may bear suitable indicia such as the arrow 62, shown in FIG- URE 4, for indicating the direction in which the discharge orifice 30 is pointed.

It will be readily apparent that the invention is capable of use as a self-contained unit, with only the parts and features thus far described, and that the dispensing head 27 may be of any conventional type adapted to discharge fluid in the form of an intermittent spray, jet or stream.

In the instant disclosure however, the invention is adapted by its foregoing features, especially for use in applying medicines or the like which should be maintained in sterile condition. It has been found that its utility and efliciency for this use may be increased by additional features and structure as hereinafter described, which cooperate with the foregoing described structure in novel beneficial manner.

Such further features and structure consist in forming the dispenser head 27 as a spray head adapted to discharge a spray of medicated liquid onto desired areas of the body, and in the provision of a protective overcap 63 for covering and maintaining sterile all normally exterior portions of the plunger and for sealing its discharge ori fice. The overcap may also be utilized for supplementing the action of the spring 17 in maintaining the plunger P fully projected and in its sealing position.

The particular form of spray head 27 here assumed by the dispensing head, and shown in FIGURES 1 and 2, is generally similar to that disclosed in the Stewart and Cooprider Patent No. 2,974,880 of March 14, 1961, being of generally cylindrical shape coaxial with the rest of the plunger and having a diametrical bore therethrough terminating at one end in the discharge orifice 30, the

other end of the bore being enlarged for frictional reception of a press fitted spinner 64. An annular distributing groove or indentation 65 in this bore encircles the spinner 64 to deliver fluid from the discharge passage 26, 26

into a series of axial grooves 66 and through tangentially directed swirl passages 67 into and through the spray orifice 30.

Because of the small size of the orifice 3t and the spray head passages 66 and 67 leading thereto, it has been found that the spray head may effectively serve as a substitute for the usual upper ball valve of the pump. While the collective size of the spray head passages is such as to substantially retard any backflow of liquid from the orifice 30 on each upstroke of the plunger, and thereby to enable the spray head 27 to perform the function of the upper pump valve, there nevertheless results at the inception of each upward plunger stroke some suck-back action of liquid from the orifice and into swirl passages 67. On the next ensuing downward or compression stroke of the plunger, the liquid initially emerging from the orifice 30 will have passed through the swirl passages 67 to have a swirling action imparted thereto such as will cause it to be discharged as a fine spray from the orifice commencing at the very inception of the discharging action. Were it not for this suck-back action above mentioned, such liquid as remained in and immediately adjacent the orifice 30 at the end of each operative pump stroke would be retained there in static position until inception of the next operative pump stroke, at which time p it would tend to be ejected simply in the form of a drop or splatter of liquid before liquid which had passed through and been subjected to the action of the swirl passages arrived at the orifice to be ejected in the form of a finally divided spray.

The overcap 63 here shown is preferably of the type which is adapted for use either as an overcap, when in the position shown in full lines in FIGURE 1, or as an applicator or localizer for the dispensed liquidspray, when in the position indicated in FIGURE 2, and in broken lines in FIGURE 1.

It will be seen that the overcap in this instance is of a generally conventional funnel shape such as is disclosed in my prior copending application above mentioned. As in said application, it is provided with a generally cylindrical sleeve portion 70 at its converging end, merging with its outwardly flaring conical portion 71. This sleeve portion 70 is internally threaded for reception on the externally threaded upper end portion 72 of the plunger above the discharge orifice thereof and the upwardly openingend of this sleeve portion will preferably be covered by a supplemental sealing cover 73 (shown fragmentarily only) of inverted cup-like shape disposed over and frictionally retained on the sleeve portion.

Below its internal threads, the sleeve portion 72 of the protective cap is formed in-teriorly of cylindrical conformation, having a radius such that its inner surface will snugly engage the marginal annular beading or rim 74 of the plunger head around the discharge orifice 30 to effectually seal such orifice. From the sleeve 63, the generally conical body of the overcap diverges downwardly and radially outwardly to a circular rim 75 which snugly receives and presents an annular seal in peripheral sealing engagement with said flange. An axially presented abutment ring 63 adjacent the rim engages the upper surface of the flange to resist inadvertent depression of the pump plunger P.

It will be apparent that when the overcap 63 is applied to the pump in the manner shown in full lines in FIG- URE 1, both the interior of the overcap as well as the externally projecting upper end portion of the plunger, are completely enclosed and protected against dust or airborne contaminants, as well as against any contact with exterior objects.

In order to adapt the overcap for its alternative use as an applicator and spray pattern localizer, the upper end of the o vercap sleeve portion 63 is formed with radially inwardly directed lugs 78 in diametrically opposed relation as is best shown in FIGURES 2 and 4-. These lugs are arranged to be snapped fitted into axially disposed grooves on diametrically opposite external sides of the spray head in the manner best illustrated in FIG. 2. The inherent resiliency of the plastic material from which the components are formed will provide the necessary resiliency for such snap fitting and disassembly of the respective parts. The several blind bores 79 in the spray 'head, seen in FIGURES l and 2, are provided for the conventional purposes of reducing the volume of material and consequently the deformation of the material incident to its curing and solidifying.

It will be understood of course that the sealing cover or cap 73 at the upper end of the sleeve will have to be removed before the use of the overcapas an applicator. Normally the said seal or cover will be operatively applied only during shipping and storage of the filled dispensers and will be removed and discarded at the time the dispenser is placed in use.

It is to be particularly borne in mind that the dispensing pump structure as herein described, in addition to its various advantages above enumerated, comprises a minimum number of separately formed parts which are required to be assembled, and that the assembly of these parts may be accomplished in a minimum number of steps.

In this connection it will be particularly noted that the plunger head diameter exceeds the external diameter of the plunger skirt 33 in the preferred embodiment only atthe location of the discharge orifice and its surrounding se-aling ring or rim 74 which is, of course, made to project some-what from the surrounding cylindrical surface portions of the plunger to afford improved sealing engagement with the overcap. However, the extent of such projections and in fact the maximum cross sectional area of theplunger head at any point is maintained with in such limits, depending upon the deformability and elasticity of the collor, as to permit the collar to be resiliently expanded and/0r deformed 'to be pressed downwardly over the upper end of the plunger head and over and past its beading 74 for operative reception and snap fitting within the cylinder extension, after the pump cylinder C, container cap 14 and plunger P are otherwise fully assembled.

Thus in assembling the several component parts of the structure it will be apparent that with the pump cylinder maintained in upright poistion, the container cap 14 may be moved axially downwardly around the upper end of the cylinder C to rest on the supporting flange thereof. After dropping the ball valve 18 into the cylinder and onto its associated valve seat, the plunger spring 17 and piston rod 25 are dropped downwardly into position. The inclined .lower ends 56 of,the splines within the cylinder enlargement or housing portion 33 guide the lower end of the spring 17 to centered position against the lower spring seat 32.i Also the spring itself, together with the conically enlarged upper end of the pump chamber .20 will guide the piston downwardly into the pump chamber. The plunger head 27 with its depending skirt 33 is then inserted downwardly over the upper end of the piston rod and pressed downwardly to urge the skirt into the cylinder extension 31 with the splines 47 and 49 of these telescopically associated spring housing sections or sleeves 31, 33 operatively associated to prevent relative rotation be-tweensthe plunger and cylinder.

The retainer collar 41 then is pressed downwardly over the upper end of the plunger head, past the radially protruding sealing beading 74 around the dischareg orifice, and thence downwardly until the collar is received and snapped fitted within the upwardly opening end of the cylinder enlargement or outer housing section. Such downward movement of the collar 41 in abutting engagement with the external rib 47 of the plunger skirt will cause the entire plunger structure to move downwardly within the pump cylinder C, thereby compressing the pump spring 17. By its expansive force, the spring 17 maintains the tapered fluid tight interconnection or coupling 58'between the piston rod and the plunger head, 'while also performing its primary function of resiliently urging the plunger upwardly or outwardly on its suction stroke.

During the operation of the invention, which is believed to be apparent from the foregoing description, the dispensers in accordance with the invention will be received by the consumer with the containers 10 filled and the container caps 14 and dispensers units applied thereto. The expansive action of the spring maintains the several seals eifective to prevent leakage of the liquid contents upwardly between the plunger and cylinder structure, being assisted in this by the snug wiping engagement between the piston and the inner wall of the pump chamber. At this time the spring pressure also maintains the sealing surface 53 of the plunger stop rib in sealing and covering engagement with the vent or breather opening 54 to prevent entry of liquid into the spring housing above the pump chamber in the event the container is fully or partially inverted.

The application of the overcap 63 in the manner indicated in FIGURE 1 and the ensuing sealing engagement of the overcap around the discharge orifice 30 of the plunger, serves both to protect the normally external portions of the plunger against contamination and to seal the orifice 30 against inadvertent discharge of liquids through the normal pump discharge passages, such as might otherwise occur incident to tilting or inversion of the dispenser. The sealed reception of the collar flange 42 in the enlarged end of the overcap-applicator 63 protects the interior of the latter, so as to maintain it as well as the plunger in fully protected sterile condition.

Also the axial abutment of the overcap with the collar tfiange 42 will supplement the action of the spring to afford means for positively resisting inadvertent down- Ward depression on the plunger such as to initiate 'an unintended or accidential pumping action during shipping or storage.

By virtue of the effective seals thus provided and including particularly the. automatic closing and sealing of the breather vent opening 54 between periods of use, the dispenser of the invention is especially adapted for use in the handling and retention, with minimum loss by evaporation or leakage, of extremely volatile liquids.

Not only are the external reciprocating portions of the plunger thus enclosed and protected in sealed relation during shipping and inoperative periods, but in addition the plunger spring 17, being thus disposed in an extensible housing or enclosure separate from the pump chamber, may be sufiiciently large and strong as to readily overcome friction resulting from closer than usual tolerance between the plunger and cylinder portions, while in no Way limiting or affecting the size of the pump chamber. Thus the pump chamber may be of such substantially smaller diameter as to permit priming of the pump with but a minimum of idle pump strokes. At the same time, the location of the substantially liquid-tight extensible spring housing between the pump chamber and the upper end of the cylinder permits the spring housing thus to function effectively as a barrier against entry of foreign particles or material to the pump chamber.

Moreover the resulting isolation of the spring housing and spring from the pump chamber and from the liquid, permits the use of the pump in connection with liquids of a highly corrosive nature without damage to the spring or such liquids.

It will be further apparent that by virtue of the coacting antirotation lugs 36 and 13 respectively, on the cylinder supporting flange and bottle neck, and the splined connection 48, 49 between the two sections 31, 33 of the spring hous ng, the plunger 27 'will be held against rotation with respect to the container 10 to facilitate the application and removal of the threaded overcap and will maintain any particular orientation that might be desired as between the container, the pump cylinder and the plunger, though no specific such orientation is required in the present embodiment of'the invention. Moreover the 10 free rotary interconnection between the container cap and its associated dispenser structure will permit free rotation of the cap to apply it to or remove it from the container.

Having thus described my invention, I claim:

1. A reciprocating pump type dispenser comprising: a pump cylinderopen at its upper end and having a valve controlled inlet port at its lower end, a plunger disposed for reciprocation in said cylinder, said plunger having a piston in snug sliding engagement with the interior of said cylinder adjacent its lower end, the upper end of said plunger projecting upwardly through the open upper end of said cylinder for manual actuation, said plunger having a portion Within the cylinder of smaller cross sectional dimension than the surrounding portion of said cylinder, a dispensing head carried at the upper end of said plunger for reciprocation therewith above and externally of the cylinder, said piston, plunger anddispensing head being provided with a valved discharge passage therethrough communicating through said pump cylinder with the inlet port, a depending skirt carried by said head and telescopically received in the upper end of said cylinder to define a liquid tight extensible spring housing above said piston and around said plunger portion, said plunger and said cylinder being provided respectively with longitudinally opposed spring seats at opposite ends of said housing, a spring encircling said plunger portion within said housing and resiliently compressed between said spring seats, said spring and said housing extending upwardly substantially above the upper end of said cylinder and stop means carried by said cylinder and by said skirt respectively for limiting the upward movement of the plunger by said spring.

' 2. A reciprocating pump type dispenser as defined in claim 1 in which said stop means of the cylinder comprises a collar fitted within the upper end of the cylinder around and in snug Wiping and guiding engagement with said plunger, and said stop means carried by the skirt comprises an outward projection around and integral with the plunger.

3. A reciprocating pump type dispenser as defined in claim 2 in which said collar and said cylinder-respectively are formed to define a snap coupling for retention of the collar within the upper end of the cylinder.

4. A reciprocating pump type dispenser comprising: a pump cylinder defining a reduced diameter lower portion and a relatively larger diameter upper portion in open communicationwith each other, said lower portion being formed with a valved inlet port, a plunger disposed for reciprocation in said lower reduced diameter portion of the cylinder and therewith defining a variable volume pump chamber, said plunger extending upwardly from said pump chamber through and above the open upper end of said cylinder for manual actuation, said plunger including a dispensing head carried at its upper end and provided with a discharge orifice, said plunger being hollow and defining a discharge passage therethrough between said orifice and the pump chamber, a skirt carried by said plunger and telescopically received in the enlarged upper portion of the cylinder to therewith define a pump spring housing, a pump spring enclosed within said housing under compression between the plunger and the cylinder to resiliently project the plunger upwardly, a collar secured within the upper end of said enlarged cylinder portion around and in snug guiding relation with the said plunger skirt, said plunger skirt having stop means thereon for abutting engagement with said collar to limit the upward projection of the plunger.

5. A reciprocating pump type dispenser as defined in claim 4 in which said pump spring is of substantially larger diameter than said pump chamber and isolated from the pump chamber by the snug sliding reception of the lower end of the plunger within the pump chamber.

6. A reciprocating pump type dispenser as defined in claim 4 in which said plunger dispensing head is separate from the rest of the plunger and releasably coupled thereto in axially aligned and abutting relation therewith, said skirt being carried by said plunger dispensing head, said plunger also including a piston rod, the lower end of which comprises a piston snugly slidably received in said pump chamber, said piston rod having a radial flange adjacent its upper end providing the spring seat for the upper end of said spring, and utilizing the upward pressure of said spring to urge the plunger dispensing head and piston rod into their assembled relation.

7. A reciprocating pump type dispenser as defined in claim 6 in which said skirt and the upper portion of said cylinder are provided respectively with interengaged axially disposed splines for preventing relative rotation between the plungerand cylinder.

8. A reciprocating pump type dispenser as defined in claim 6 in which said collar and said stop means respectively are provided with relatively abutting interengaging sealing surfaces pressed into sealing engagement by said pump spring, said collar and said upper portion of the cylinder also being provided with relatively opposed sealing means pressed into operative engagement by the pump spring for preventing leakage of liquid between them.

9. A reciprocating pump type dispenser comprising: a pump cylinder having a reduced diameter pump chamber at its lower end and a relatively enlarged diameter spring housing section at its upper end coaxial with said pump chamber and in open communication therewith, a plunger disposed for reciprocation in said cylinder and comprising a tubular piston rod having a piston at its lower end disposed for reciprocation in said pump chamber, said piston rod extending upwardly through the enlarged upper portion of said cylinder in radially spaced relation from the inner surface of said upper cylinder, a dispensing head carried at the upper end of said piston rod and provided with a liquid discharge orifice, said plunger head, piston rod and piston being formed to define a discharge passage extending between said orifice and said pump chamber, said plunger head being provided with a skirt encircling said piston rod in coaxial spaced relation therefrom, said skirt being telescopically received in the said enlarged diameter upper portion of the cylinder and therewith defining a pump spring housing around the piston rod, a coil spring disposed around the piston rod within said housing and under axial compression between the plunger and cylinder, said spring housing being substantially isolated from the pump chamber by said piston, and cooperating stop means carried by said plunger and said cylinder respectively for limting the upward movement of the plunger.

10. A reciprocating pump type dispenser as defined in claim 9 in 'which said plunger head and said piston are separable, being coupled together in axial abutment, said plunger head being provided with a radially projecting flange adjacent its upper end, the upper end of said spring abutting against said flange, said plunger head skirt carrying the stop means of said plunger, said spring and said stop means normally resiliently maintaining said plunger head and piston rod in their assembled relationship.

11. A reciprocating pump type dispenser as defined in claim 10 wherein said cylinder includes a collar releasably secured in the upper end thereof around and in snug guiding relation with the said piston skirt, said collar functioning as one of said cooperating stop means, the other such means being carried by the plunger skirt and comprising an annular radially projecting rib around the plunger skirt, said rib and said collar having relatively axially abutting sealing surfaces for preventing leakage of liquid between the collar and the depending skirt, said collar and said cylinder also having axially abutting sealing surfaces for preventing leakage of liquid therebetween.

tional shape, whereby said collar may be passed down over the upper end of the plunger head and assembled into the upper end of the said cylinder-to secure the separate parts of theplunger and plunger spring in assembled relation with each other and with the cylinder.

13. A reciprocating pump type dispenser comprising: a container having a threaded neck defining an outlet opening, a closure cap having a threaded skirt operatively engaging said neck and a medially apertured top overlying the end of said neck, a pump cylinder extending through said medially apertured closure top and having a radial supporting flange secured between said top and the end of said bottleneck, said radial supporting flange including a depending skirt encircling the upper end of said container neck above the threads thereof, said skirt and said neck being formed with relatively intermeshing lugs for preventing relative rotation between the pump cylinder and the container, the upper end of said cylinder projecting above the closure top, a collar fixed to said upper end of the cylinder and having a radially projecting flange overlying said closure top, said closure top being freely rotatable on said cylinder between the said flanges, a pump plunger operatively disposed for reciprocation in said cylinder, said plunger including a piston insnug fluid tight sliding engagement with said cylinder interior adjacent the lower end of the cylinder to therewith define a variable volume pumping chamber, said plunger extending upwardly through and above said cylinder and closure top and having a discharge head carried at its upper end, said discharge head communicating through said plunger with said pump chamber, a protective overcap removably threaded onto said plunger above the container closure cap, said cylinder and said plunger respectively being formed with mutually interengaged splined portions above said pump chamber for cooperating with said lugs to prevent rotation of the plunger with respect to the container as the said protective overcap is threaded onto or removed from the plunger.

14. The combination of elements defined in claim 13 in which said plunger head above the container cap is provided with a generally radially directeddischarge orifice, the plunger head being formed with a sealing rib surrounding said orifice and adapted for sealing engagement with the inner peripheral surface of the protective overcap.

15. A reciprocating pump type dispenser comprising:

a pump cylinder defining a cylindrical pump chamber at its lower end and a relatively larger diameter spring housing section above and in axial alignment with the said pump chamber, a valved inlet port communicating with said pump chamber, a plunger having a relatively small diameter lower end portion for snug sliding reception in said pump chamber and a relatively larger diameter portion for snug fluid tight sliding reception in said upper portion of the cylinder, said cylinder being formed with an axially upwardly presented annular spring seat around the upper end of said pump chamber, said plunged including a relatively reduced diameter portion within and spaced radially from said enlarged upper portion of the cylinder, an upper spring seat carried by said reduced diameter portion of the plunger within the relatively enlarged diameter portion of the cylinder and spaced above said lower spring seat, a coil spring encircling said reduced diameter portion of the plunger and axially compressed between said spring seats, an annular retainer collar, the upper enlarged end portion of said plunger being of substantially uniform external diameter and cross sectional shape for reception and downward movement over its upper end of said retainer collar, said collar encircling and guiding the enlarged upper portion of the plunger in its reciprocating movement, said plunger having stop means disposed for axial abutment with said collar to limit the 13 upward projection movement of the plunger by its said spring.

16. The combination defined in claim 15 in which said collar is snap fitted into the upper end of said pump cylinder in sealing engagement both With said cylinder and with said plunger in the upwardly projected position of the latter.

17. The combination of elements as defined in claim 15 in which the flange of said collar overlies and abuts against the upwardly presented end of said cylinder, said overcap being threaded onto the plunger and into axial abutment with said flange, thereby urgingsaid collar downwardly toward sealing engagement against said stop means on the plunger.

18. A reciprocating pump type dispenser comprising: a pump cylinder defining a reduced diameter lower portion and a relatively larger diameter upper portion in open communication with each other, said lower portion being formed with a valved inlet port, a plunger disposed for reciprocation in said lower reduced diameter portion of the cylinder and therewith defining a variable volume pump chamber, said plunger extending upwardly from said pump chamber through and above the open upper end of said cylinder for manual actuation, said plunger including a dispensing head carried at its upper end and provided with a discharge orifice, said plunger being hollow and defining a discharge passage therethrough between said orifice and the pump chamber, a skirt carried by said plunger and telescopically received in the enlarged upper portion of the cylinder to therewith define a pump spring housing, a pump spring enclosed within said housing under compression between the plunger and the cylinder toresiliently project the plunger upwardly, a collar secured within the upper end of said enlarged cylinder portion around and in snug guiding relation with the said plunger skirt, said plunger skirt and said collar having relatively opposed sealing and stop surfaces positioned for sealing engagement at the upper end of the plunger stroke, said collar and said cylinder being formed to define a vent opening outwardly through the cylinder and opening inwardly through said sealing and stop surface of the collar, in position for closure by the said sealing and stop surface of the plunger skirt.

19. The combination defined in claim 18 in which said vent is defined by an annular space encircling said collar between the collar and cylinder, a vent passage extending outwardly from said space through the cylinder and a further vent passage opening inwardly from said space through said sealing and stop surface of the collar.

References Cited by the Examiner UNITED STATES PATENTS 2,185,534 1/1940 Bernhardt 222-321 2,985,382 5/1961 Coplan 222182 X 3,128,018 4/1964 Corsette et al. 222321 FOREIGN PATENTS 942,161 4/ 1956 Germany.

LOUIS J. DEMBO, Primary Examiner.

CHARLES R. CARTER, Examiner. 

1. A RECIPROCATING PUMP TYPE DISPENSER COMPRISING: A PUMP CYLINDER OPEN AT ITS UPPER END AND HAVING A VALVE CONTROLLED INLET PORT AT ITS LOWER END, A PLUNGER DISPOSED FOR RECIPROCATION IN SAID CYLINDER, SAID PLUMBER HAVING A PISTON IS SNUG SLIDING ENGAGEMENT WITH THE INTERIOR OF SAID CYLINDER ADJACENT ITS LOWER END, THE UPPER END OF SAID PLUNGER PROJECTING UPWARDLY THROUGH THE OPEN UPPER END OF SAID CYLINDER FOR MANUAL ACTUATION, SAID PLUNGER HAVING A PORTION WITHIN THE CYLINDER OF SMALLER CROSS SECTIONAL DIMENSION THAT THE SURROUNDING PORTION OF SAID CYLINDER, A DISPENSING HEAD CARRIED AT THE UPPER END OF SAID PLUNGER FOR RECIPROCATION THEREWITH ABOVE AND EXTERNALLY OF THE CYLINDER, SAID PISTON, PLUNGER AND ISPENSING HEAD BEING PROVIDED WITH A VALVE DISCHARGE PASSAGE THERETHROUGH COMMUNICATING THROUGH SAID PUMP CYLINDER WITH THE INLET PORT, A DEPENDING SKIRT CARRIED BY SAID HEAD AND TELESCOPICALLY RECEIVED IN THE UPPER END OF SAID CYLINDER TO DEFINE A LIQUID TIGHT EXTENSIBLE SPRING HOUSING ABOVE SAID PISTON AND AROUND SAID PLUNGER PORTION, SAID PLUNGER AND SAID CYLINDER BEING PROVIDED RESPECTIVELY WITH LONGITUDINALLY OPPOSED SPRING SEATS AT OPPOSITE ENDS OF SAID HOUSING, A SPRING ENCIRCLING SAID PLUNGER PORTION WITHIN SAID HOUSING AND RESILIENTLY COMPRESSED BETWEEN SAID SPRING SEATS, SAID SPRING AND SAID HOUSING EXTENDING UPWARDLY SUBSTANTIALLY ABOVE THE UPPER END OF SAID CYLINDER AND STOP MEANS CARRIED BY SAID CYLINDER AND BY SAID SKIRT RESPECTIVELY FOR LIMITING THE UPWARD MOVEMENT OF THE PLUNGER BY SAID SPRING. 